Stuart's shrub frog ( Pseudophilautus stuarti)

Color of this one has been changed to match with the leaf litter.

English: Stuart's shrub frog
Binomial: Pseudophilautus stuarti
Sinhala: ස්ටුවර්ට්ගේ පඳුරු මැඩියා

Philautus stuarti is an endemic species of amphibian restricted to the knuckles region of Sri Lanka. This species was first described from the Coberts Gap region of knuckles by Dr. Meegaskumbura and Mr. Kelum Manamendra-Archchi in 2005. Elevation above the sea level of their observed location was about 1245m (Meegaskumbura and Manamendra-Arachchi 2005).

This species occurs in cloud forests with a good canopy cover. There is a similar species of amphibian which lives in the same knuckles region, namely Pseudophilautus mooreorum with the same body color. But P. stuarti can be easily distinguished from P. mooreorum by the prominent supratympanic fold and sharp cathal edge.

In addition to that, a population of shrub frogs named Pseudophilautus viridis which is morphologically more similar to P. stuarti occurs in the central highlands of Sri Lanka. Phylogenetic analyses have revealed that these both species are genetically more related to each other. These two populations have been geographically separated by Mahaweli River valley that separates central hills from the knuckles mountain region(Meegaskumbura and Manamendra-Arachchi 2005). It is believed that this long term geographical separation has led to common ancestor species of frogs to divide into two geographical groups and then to evolve them as two new separate species namely P. viridis and P. stuarti.

Above photographed ones were also observed in the adjoining forest of Deanston Conservation Center in the knuckles region which is about 4 km away from the Coberts Gap. Observed location was at a height of about 1320m above the sea level. We can believe that the reminding conserved forest segments of knuckles region provides some protection for the species. But due to the limited distribution, it falls in to the category of ‘Endangered’ in the IUCN Red List.

Referances:

• Meegaskumbura, Madhava, and Kelum Manamendra-Arachchi 2005 Description of Eight New Species of Shrub Frogs (Ranidae: Rhacophorinae: Philautus) from Sri Lanka. The Raffles Bulletin of Zoology 12: 305–338.
• The IUCN Red List of Threatened Species(tm) 2015-4 - http://www.iucnredlist.org
• Manamendra-Arachchi, K. & R. Pethiyagoda (2006): Sri Lankan amphibians [in Sinhala]. – WHT Publications, Colombo